The change in mode status of the Attached Pressurized Module (APM), termed a mode transition, is due to the need of changing the APM configuration triggered by nominal or contingency events, i.e: initial system activation and further de/reactivation, payload activation, crew, ground or station initiated mode changes, etc.
Past simulations of the APM Cabin Air Loop, for individual operational modes, have been performed by Dornier. This paper presents the results of the hydraulic and thermal analyses of the APM Cabin Air Loop for mode transition with the new version of the European Space Agency (ESA) supported software EcosimPro. The range of analysis has now been extended to long duration simulation of transitions between modes, which was impractical in the past. The transitions cover both operational and non-operational modes, with rapid changes in boundary conditions, as heat loads, air and coolant mass flows, crew metabolic heat, International Space Station (ISS) supplied air interface temperature and relative humidity, etc.